---
tag: ZD6BATCYS6
kind: concept
name: Strength (mathematical logic)
aliases: [strength-mathematics]
sources:
  - wikipedia: en:28870339@r1294787021
    locator: Strength (mathematical logic)
    note: adopted
    mention: wikipedia://en/28870339
    sections: [Summary]
same_as:
  wikidata: Q1989404
  wikipedia: Strength (mathematical logic)
inventory: [XJYTE69321]
---

## Summary

The relative **strength** of two systems of formal logic can be defined via model theory. Specifically, a logic $\alpha$ is said to be as strong as a logic $\beta$ if every elementary class in $\beta$ is an elementary class in $\alpha$.